Power-transmission belt



May 5, 1925. I

. F. W. BROWNING POWER TRANSMISSION BELT Filed Aug. 5, 1922 Patented May 5, 1925.

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Applicatioufiled August 5, 1922. Serial No. 579,945.

To all whom it may concern:

Be it known that I, Fnuronun W. BROWN- ING, a citizen of the United States, and resident of Kingsport, Sullivan County, Tennessee, have invented an Improvement in Power-Transmission Belts, of which the following description, in connection with the with cement, to make either single or multiple ply leather belting, the grain side of the leather being on the outside of the multiple ply belts.

I have discovered that the coefficient of friction bet-ween the belt and its driving and V driven pulleys is increased by partially removing the hard pebbly grain surface of the epidermis of the leather, preferably by abrasion such as by running it past a rotating sand paperwheel, and that a belt so treated will transmit more power under less tension and last longer than untreated belts with a hard grain surface.

In practising the invention, the belt may be constructed in the usual way, in convenient lengths, say of 300 feet, and passed at a relatively slow speed under a rotating sand paper wheel having a peripheral speed of perhaps three or four thousand feet per minute, the pressure of the wheel upon the belt being regulated to suit the sharpness of the sand and the hardness of the particu' lar leather so as to smooth off the slight irregularities of the grain surface and produce a velvety smooth finish as distinguished from the hard shinyfinish of the original grain surface.

Any suitable abrading apparatus may be utilized for performing the process, but I prefer to use a machine of the type shown in the accompanying illustrative diagram or drawing, wherein a sand paper wheel 11 is mounted upon a horizontal shaft 12 journaled in bearings 13 which maybe adjusted vertically ts vary the height of the wheelabove the table 14 to suit the thickness of the belt. A pressure roller 15 of suitable dimensions is mounted parallel to the under side of the sand paper wheel and arranged to be automatically adjustable toward and from the latter to suit slight irregularities in the belt. This automatic adjustment may be provided by arranging the supporting bearings 16 for the pressure roller so as to have a slight vertical sliding movement in suitable guides 17, being pressed upward by springs 18. The compression of the springs may be increased or decreased to suit the character of the leather under treatment by any suitable means, such as the cams 19 on the shaft 20 which may be turned by the hand lever 21. Both the sandpaper wheel and pressure roller are preferably driven by suitablepower means, such as the belts 2-2, 23 and 24, from the motor 25. Any suitable feeding device for controlling the speed ofthe belt past the sand. paper wheel may be utilized, such as the oppositely geared feed rolls 26, 27, which in the illustrative apparatus, are driven by the belt 28. The feed rolls may be separated to release the belt by any suitable means, such as'the hand lever 29 which raises the upper roll when raised.

After the 'abrading operation is completed 1 preferably coat the abraded surface with a light coating of any suitable pigment or blacking to fill the pores of the grain to improve its appearance, and increase its adhesion to the pulleys.

The invention is not restricted to the par.-

ticular means shown and described for treating the belt, nor to a belt treated by the particular process described, the means and processes shown and described being illustrative only.

What I claim and desire to secure by Letters Patent is as follows:

1. A power transmission belt having a grain leather working surface treated uniformly by abrading to thereby increase the adhesion between the belt and the pulleys over which it may run.

2. A multiply power transmission belt having a grain leather working surface treated by abrading to remove part of the epidermis throughout its length and thereby increase the adhesion between. the belt and the, pulleys over which it may run.

3 power transmission belt comprising a plurality of assembled strips having a,

grain leather working surface treated by abrading to remove the objectionably hard pebbly grain over the entire surface and thereby increase the adhesion between the belt and the pulleys over which it may run.

4. A leather belt for power transmission purposes having a grain side working surface With a portion of the epidermis removed uniformly from its entire surface whereby to increase the coeflicient of friction between the belt and a pulley.

In testimony whereof, I have signed my name to this specification.

FLETCHER W. BROWNING. 

